Mosquito Species Composition and Plasmodium vivax infection Rates for Korean Army Bases near the Demilitarized Zone in the Republic of Korea, 2011

Abstract

Vivax malaria is a significant military and civilian health threat in northern Republic of Korea (ROK). Mosquito collections were performed at two ROK army installations, Paju near the demilitarized zone (DMZ) using black light traps in 2011. The DMZ, a 4 km wide border, is the northernmost point of the ROK and separates the ROK from the Democratic People's Republic of Korea (DPRK). Anopheles spp. were identified by polymerase chain reaction and screened for Plasmodium vivax sporozoites. Of 4,354 female Anopheles mosquitoes identified, Anopheles kleini (61.8%) was the most frequently collected, followed by Anopheles pullus (16.0%), Anopheles belenrae (9.0%), Anopheles sinensis (7.4%), Anopheles sineroides (4.2%), and Anopheles lesteri (1.6%). Anopheles kleini, An. pullus, and An. sineroides showed the highest population densities in June, whereas population densities were highest for An. belenrae, An. lesteri, and An. sinensis in August. The maximum likelihood estimation (estimated number of positive mosquitoes/1,000) for P. vivax was highest for An. lesteri (28.9), followed by An. sineroides (23.3), An. belenrae (15.8), An. sinensis (9.6), An. pullus (5.8) and An. kleini (4.2). The seasonal maximum likelihood estimation (MLE) values were variable among Anopheles species. Anopheles belenrae, An. Pullus, and An. sineroides showed the highest seasonal MLE's in July, whereas An. lesteri and An. sinensis exhibited the highest seasonal MLEs in September and An. kleini during August. This is the first report implicating An. sineroides as a vector of P. vivax in the ROK, and extends our knowledge of the distribution and potential role in malaria transmission.